Assays for determinig the pathogencity of toxoplasma infections

Abstract

The present invention describes methods of identifying high-risk populations or individuals who have positive serology for T. gondii. These methods include obtaining a biological sample from a subject; determining the level of T. gondii cyst antigen antibody in the biological sample; and characterizing the biological sample in at least one of three categories.

1 . A method of identifying a high-risk population or an individual who has positive serology for  T. gondii  comprising the following steps:
 a. obtaining a biological sample from a subject; and   b. determining the level of  T. gondii  cyst antigen antibody in the biological sample.   
     
     
         2 . The method of  claim 1  further comprising the steps of characterizing the biological sample in at least one of the three categories: (i) high  T. gondii  cyst antigen antibody level; (ii) low  T. gondii  cyst antigen antibody level; or (iii) substantially free  T. gondii  cyst antigen antibody level. 
     
     
         3 . The method of  claim 1  wherein the  T. gondii  cyst antigen is a MAG1 antigen. 
     
     
         4 . The method of  claim 3  wherein MAG1 antigen is selected from the group consisting of MAG1_4, MAG1_5, or a combination thereof. 
     
     
         5 . The method of  claim 1  wherein the level of  T. gondii  cyst antigen antibody is determined using ELISA 
     
     
         6 . The method of  claim 5  wherein the biological sample has a high  T. gondii  cyst antigen antibody level of greater than 0.5 OD. 
     
     
         7 . The method of  claim 5  wherein the biological sample has a low  T. gondii  cyst antigen antibody level in the range of 0.06 to 0.49 OD. 
     
     
         8 . The method of  claim 5  wherein the biological sample has a substantially free  T. gondii  cyst antigen antibody level in the range of 0 to 0.059 OD. 
     
     
         9 . The method of  claim 6  comprising an additional step of monitoring the subjects to avoid disease risk. 
     
     
         10 . The method of  claim 9  comprising an additional step of treatment to prevent serious disease. 
     
     
         11 . The method of  claim 2  wherein the individual is a pregnant woman. 
     
     
         12 . The method of  claim 11  wherein the biological sample is characterized as having (i) high  T. gondii  cyst antigen antibody level and comprising the further step of informing the pregnant woman of an option of an abortion. 
     
     
         13 . The method of  claim 2 , wherein the individual is a immunocompetent individual. 
     
     
         14 . The method of  claim 13  wherein the biological sample is characterized as having (i) high  T. gondii  cyst antigen antibody level and comprising the further step of monitoring or treating the immunocompetent patient to avoid the incidence of ocular toxoplasmosis or mental disorder. 
     
     
         15 . The method of  claim 2  wherein the biological sample is characterized as having (i) high  T. gondii  cyst antigen antibody level and comprising the further step of monitoring or treating the high risk population to avoid the incidence of ocular toxoplasmosis or mental disorder. 
     
     
         16 . The method of  claim 2 , wherein the individual is a child. 
     
     
         17 . The method of  claim 16 , wherein the biological sample is characterized as having (i) high  T. gondii  cyst antigen antibody level and comprising the further step of treating the child to reduce an incidence of sequelae. 
     
     
         18 . A kit comprising a  T. gondii  cyst antigen antibody and instructions describing the method of  claim 1 . 
     
     
         19 . The kit may further comprise a  T. gondii  organism antibody.